• Ocean and Polar Research
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• 제23권2호
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• pp.133-139
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• 2001

Ocean currents estimated from sea height anomalies derived from inter-calibrated TP/ERS are compared with daily mean currents measured with satellite-tracked drifters. The correlation coefficient between the geostrophic current from TP/ERS and surface current at 15 m depth from drifter tracks was found to be about 0.5. Due to the limitation of satellite ground tracks, small scale eddies less than 80 km are poorly resolved from TP/ERS. One of the interesting results of this study is that coastal currents along the eastern coast of Korea were well reproduced from sea height anomalies when the coastal currents were developed in association with eddies near the South Korean coast. The eddy kinetic energy (EKE) estimated from drifters, TP/ERS, and a numerical model are also compared. The EKE estimated from drifters was about 22 % higher than EKE calculated from TP/ERS. The pattern of low EKE level in the northern basin and high EKE level in the southern East Sea is shown in the EKE estimates derived from both the drifters and TP/ERS.

• 한국환경과학회지
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• 제19권4호
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• pp.399-406
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• 2010

Based on the Results of Annual Monitoring Report of Korean Marine Environment in 2006, it was shown that the coastal area of the East Sea around Korean peninsula could be clearly divided into two parts: the area of upwelling and the North Korean Cold Current. In the upwelling area, the chlorophyll-a and nutrients were increased by the influence of the decrease of temperature and the increase of salinity. These mean that the appearance of cold water due to the upwelling causes nutrient rich water and also resulted in the high productivity.

• 한국수산과학회지
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• 제30권6호
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• pp.997-1004
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• 1997

The effect of the oceanic condition on variations of the catches of Alaska pollack (Theragra chalcogramma) in the East Sea (the Japan Sea) is examined using monthly catches data of this fish and temperature data during 1972 to 1991. Since 1973 the catches of Alaska pollack have gradually increased, showing a peak in 1981, and then rapidly decreased after 1986. A significant negative correlation was found between variations of the catches and the temperature at 50 m depth offshore Mukho. In 1981, the year of the highest catches in the study period, the water mass in the Eastern Korean Coastal Sea of the East Sea was extremely cold, while the year of poor catch, 1979, was much warmer than the annual mean temperature. The results show that the temperature variations around the Eastern Korean Coastal Sea play an important role in the variations of the catches of Alaska pollack, implying that the effect of the Tsushima Warm Current is also very important.

• 한국환경과학회지
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• 제17권12호
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• pp.1403-1411
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• 2008

Wangdol-cho, located 23 km offshore of Hupo in southwest of East Sea, is underwater rock floor, called to Wangdol-Am or Wangdol-Jam and has three tops as Mat-Jam, Middle-Jam and Set-Jam. The composition, abundance, diversity and community structure were investigated in winter and summer in 2002 around Wangdol-cho. The temperature around the Northwest and Southeast part of Wangdol-cho was influenced by the North Korea Cold Current (NKCC) and East Korea Warm Current (EKWC), respectively. Nutrient and chlorophyll-a concentration were higher at the top of Wangdol-cho than other area. A total of 41 genera and 78 species of phytoplankton were identified. The average cell abundance of phytoplankton in winter and summer were $286{\times}10^3\;cells/m^3,\;432{\times}10^3\;cells/m^3$ respectively. The largest community was Bacillariophyta containing 52 taxa. The dominant species were Lauderia anulata and Coscinodiscus spp. which preferred cold water in winter. In contrast, warm water species such as Rhizosolenia stolterfothii and Ceratium spp. were dominant in summer. The average species diversity index of phytoplankton in winter was higher than that in summer. According to dominant species and standing crops, phytoplankton community resulted in a clear separation. One group was western area, which showed low density, and the other was eastern area, which showed the higher density. The abundance and species composition of phytoplankton. were affected by topological characteristics around Wangdol-cho.

• 한국해안해양공학회지
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• 제9권3호
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• pp.105-114
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• 1997

바람은 동해의 순환에 기여하는 중요한 외력이다. 1.5층 및 2.5층 감쇠중력 모형을 이용하여 동해의 순환을 시뮬레이션하여 대마난류의 분기, 동해안의 동한난류의 분기, 동한만 및 동해북부에서의 반시계 방향성 순환현상을 기존순환모형도와 비교하였다. 상층과 하층의 양상은 동해의 중앙부를 제외하고는 유사하였는데 극전선이 다음과 같이 서로 다른 두양상을 제시한다. 극전선의 북측의 주양상은 대부분의 계절에 발생하는 3개소의 반시계방향 와동이며 이 와동의 내측연안을 따라서 북한류와 리만한류가 흐른다. 극전선의 남측에서 상하 양층의 해류체계는 겨울과 봄의 상층순환을 제외하고는 시계방향 순환이다. 한국과 러시아 연안을 따라 류속구조는 순압적이나 동해중부는 경압적이다. 바람응력의 계절적 변화와 Ekman 수송(suction/pumping)을 시간변화를 갖는 공간적평균과 공간적변화를 갖는 시간적으로 수정된 바람응력을 부여함으로서 조사하였다. 동해의 서측과 북서측 해역의 반시계방향 와동의 형성에 있어서 바람응력 컬(curl)에 의한 국지적인 Ekman suction/pumping이 중요함을 확인하였다

• Fisheries and Aquatic Sciences
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• 제3권2호
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• pp.97-110
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• 2000

To investigate characteristics of water masses and current structures around Noto Peninsula located in south-east coastal region of the East Sea, observation results of CREAMS (Circulations Research of the East Asian Marginal Seas) cruise and data report of oceanographic observation (Japan Meteorological Agency) in June, 1995 and 1996 were used. Water mass showing characteristics of Tsushima Warm Current (TWC) exists over the continental shelf. The depth is shallower than 200m and its width and thickness are 190km and 200m, respectively. Minimum level of dissolved oxygen occurred at the layers of maximum salinity. In the current structure, a noteworthy phenomenon is that the positions of the high-salinity water (more than 34.6 psu) match well with the distributions of the southwestward flow. In June of 1995 and June of 1996, a southwestward flow were separated into two parts along line C and line G. Current directions derived from the temperature and salinity match well with the distributions of the geostrophic currents in the vertical sections. The isothermal lines and the isohaline, which exist horizontally along the coastal area of the Japan, change abruptly at the frontal area of the Noto Peninsula, then turn toward the center of the East Sea. The dynamic depth anomalies centering around the region far northwest of the Noto Peninsula were relatively high, compared to those of other regions. The isopycnic surface (sigma-t, 25.8) existed near the surface in the central part of the East Sea, but, at the depth of 100m, the isopycnic surface was found in the coastal waters.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2003년도 추계종합학술대회
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• pp.339-342
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• 2003

1993년에서 1997년까지의 위성고도계 자료(Topex/Poseidon)를 이용하여 한반도 주변해역의 해면 변화와 표층흐름을 조사하였다. 해면변화를 보면, 동해에 비해서 서해와 남해는 항상 상대적으로 높았다. 전 조사 기간에 걸쳐서 서해는 북부와 남부 해역에서 각각20-30cm와 18-24cm의 변화범위를 보였으며, 남해는 제주도 북서부 해역에서는 15-20cm 그리고 쓰시마섬 남서부 해역에서는 10-15cm의 변화범위를 각각 나타내었다. 서해의 경우에 황해난류의 표층 유입류와 해저 지형류의 영향을 받아 높은 변화를 보였다. 남해의 경우는 변화가 일어나는 두 곳 모두가 근원적으로는 쿠로시오 해류의 흐름에서 분기된 지류들의 흐름(제주난류와 동한난류) 때문에 해면변화를 보였다. 표층 순환은 동해에서 북한한류, 동한난류와 쓰시마 난류와 관련한 세가지 와류운동이 두드러지게 나타났다. 와류운동은 기본적으로 표층 순환에서 해류의 영향을 받았다; 원산만 앞바다의 반시계방향(0.03 cm/sec)의 흐름은 북한한류, 울릉도 남서쪽 해역의 시계방향(0.06 cm/sec)의 흐름은 동한난류, 그리고 쓰시마섬 북서쪽 해역은 쓰시마 난류와 각각 관계되어있는 것으로 보인다.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2004년도 춘계학술발표회
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• pp.89-92
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• 2004

포텐셜와도는 해류의 순환을 설명하는데 유용하게 활용된다. 동해에서 포텐셜와도의 분포 특성을 이용하여 쓰시마난류를 포함한 상층부의 해류순환을 설명하였다. 상층부를 표층부분과 쓰시마난류의 분포 층 그리고 수온약층 분포 수층으로 구분하였다. 극전선남쪽은 쓰시마난류가 해류순환의 중심을 형성하며, 포텐셜와도는 쓰시마난류와 극전선의 분포 특성을 잘 나타내어준다. 포텐셜와도의 분포로부터, 극전선 북쪽은 일본 분지와 그 서쪽해역의 순환 세포로 구분된다.

• 한국해양학회지:바다
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• 제24권3호
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• pp.429-435
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• 2019

연안에서 해표면고도를 정확하게 측정하도록 특별히 설계된 SARAL/Altika위성에 의해 관측된 해류를 비교 검정하기 위해 2015년 3월부터 2년간 위성추적 뜰개가 동해 북부 해상에 투하되었다. 해표면 고도 측정 위치에서 반경 20 km 이내에 위치한 뜰개(30분 간격으로 GPS로 위치 관측)와 비교한 결과, 수심 200 m 보다 얕은 해역에서 외해와 유사하게 높은 상관관계를 가진 것으로 나타나, 해류의 직접 관측이 어려운 동해 북부의 연안류의 시간 변동을 관측할 수 있게 되었다. 리만 해류는 일년 년중 시베리아 연안을 따라 남하하는 해류로 관측되었으며, 북한 한류는 여름철에만 남향하는 해류를 보였다. 북한 한류는 무수단곶 이남에서는 주로 남향류를, 무수단곶 이북에서는 무수단곶 근해에서의 에디 존재 유무에 의해 방향이 결정되는 것으로 연구되었다.

• 한국환경과학회지
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• 제17권2호
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• pp.141-148
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• 2008

In order to investigate the effect of inflow of Yangze river on the distribution of chlorophyll-${\alpha}$, the results of serial oceanographic observation during 2000-2005 were used. The oceanographic conditions in the northern East China Sea is influenced by the Tsushima Warm Current and low saline water derived from the Yangze river. The distributions of these water masses vary significantly by the season in the northern East China Sea. The sea surface temperature and salinity were stable and concentrations of chlorophyll-${\alpha}$ were low in the eastern part of $126^{\circ}E$. On the contrary, the salinity was significantly influenced by the low saline water derived from Yangze river with the high concentrations of chlorophyll-${\alpha}$. It is suggested that the low saline water inflowed from the Yangze river affects high concentrations of chlorophyll-${\alpha}$ in the northern East China Sea in summer.